The present invention concerns a fuel assembly for gas-cooled nuclear reactors, particularly fast breeders, which consists of a multiplicity of fuel rods which are fastened to a rod holding plate provided with passage holes for the coolant, and are each connected via a perforated end cap to a fission gas exhaust system. Such fuel assemblies are called in the literature also vented fuel assemblies. In them, the fission gases therefore do not remain in the interiors of the respective fuel rods, but are led off to a fission gas collecting system so that no excessive or undesirable overpressure can build up in the interior of the fuel rods and a possible poison effect of the fission gases remains within limits.
According to the prior state of the art, the individual fuel rods of such a fuel assembly are connected with the upper fuel rod holding plate of the fuel assembly by a screw connection or by soldering or welding and the venting canals in the end caps are soldered to a separate gas conduction grid. For carrying out these soldering operations, the fuel assembly must be brought at least partially into a soldering oven, so that all the solder joints are made simultaneously.
This manufacturing method not only requires a large expenditure of technical means, but also makes replacement of individual fuel rods difficult in case a soldered connection should become leaky, for instance.
The problem therefore arises to simplify these fastening and joining techniques, to the extent possible, so that easy replaceability of individual fuel rods remains assured in all cases. This replaceability should, in particular, have no detrimental effect on the other fuel rods of the fuel assembly.